Triton X-1˹˹based cloud point extraction has been demonstrated to be an advantageous approach for the recovery of nanosized copper oxide[1-3] (NCO) from rice. Nano Copper Oxide in the initial aqueous solution was complexed with sodium diethyldithiocarbamat (NaDDC) . Dilution of the surfactant-rich phase with acidified methanol was performed after phase separation and nano Copper Oxide contents were measured by UV-Visible spectrophotometric technique. The variables affecting the cloud-point extraction were optimized using Tauguchi orthogonal array design. The effective factors including pH, extraction time, temperature extraction ,amount of the triton X- 100 , concentration of salt and concentration of the ligand were studied and optimized . Under the optimized condition , the calibration graph was linear in the range of 1-30µg.L -1 for Nano Copper Oxide. The limit of detection (LOD) was 0.93 µg.L -1 . The relative standard deviation (RSD % n=7) for the determination of 10 µg.L -1 was 4.2%. The proposed method has been applied successfully to determine the trace amount of nano copper oxide in some of rice samples.

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